Table 3  Adjusted and unadjusted odds ratios against the risk factors
Risk factors  Unadjusted odds ratio (95% CI)  Adjusted odds ratio (95% CI)
Social distancing of six feet or more   
     Almost always (more than 90%)    1  1
     Commonly (about 50%)    0.32 (0.10-0.97)    0.15 (0.07-0.32)  
     Sometimes (about 25%)  0.40 (0.01- 0.21)    0.08 (0.03-0.19)  
     Rarely (less than 10%)  0.20 (0.03-1.21)  0.15 (0.05-0.46)  
Hand hygiene frequency   
     Once every hour    1  1
     Every 2-3 hourly  0.80 (0.24-2.68)  0.36 (0.15-0.82)  
     Every 3-4 hourly    0.35 (0.11-1.10)    0.08 (0.03-0.22)  
     Less than that  0.25 (0.07-0.80)  0.14 (0.06-0.34)  
Ensuring N-95 mask fitness  2.04 (0.83-4.99)    0.35 (0.18-0.66)
Resident doctors  0.27 (0.05-1.34)    0.39 (0.19-0.79)